The present invention relates to a vacuum packing configuration comprising a pneumatically or hydraulically expandable first packing part as well as a second packing part against which the first is stressed, forming a seal.
The present invention relates furthermore to vacuum treatment installations with a stator with an interior volume substantially having the shape of a body generated by revolution, for a rotor comprising a multiplicity of workpiece holding fixtures spaced apart with respect to a rotational drive axle, with the stator comprising a multiplicity of treatment and/or transfer-through ports communicating with the interior volume for workpieces of a workpiece holding fixture, and in which, further, each of the workpiece holding fixtures driven on the rotor is directly positionable at each of the ports on the stator and in each instance a pneumatically or hydraulically actuatable packing configuration hermetically seals the workpiece holding fixture at the port against the remaining interior volume of the stator.
A vacuum packing configuration of the above described type is known from European patent application EP 0 555 764 or U.S. Pat. No. 5,415,729. It comprises a metallic bellows tube which forms a sealing structure via a part comprising a resilient material, especially intended for this purpose, such as for example a polymer such as TEFLON material (TEFLON is a trademark) or an elastomeric material, against the passive second packing part.
This provision is often disadvantageous because of the following reasons:
Often the sealing tightness required in each instance for a pressure-expanded metallic bellows having a relatively large bellows front face, is dimensionally stable only if the front face is provided with a resilient part. PA0 The resetting force which drives it back with a pressure relief due to the spring bellows effect, is relatively low and the return position of the bellows is relatively indeterminate. PA0 A bellows is extremely costly, if not unsuitable, for the realization of long sealing contours. PA0 Bellows are subject to resonance phenomena during operation, which drastically reduce their service life due to the resulting, possibly high-frequency, alternating loadings.